Conventionally, there have been developed various compact digital cameras and digital video units that incorporate an imaging module including an imaging lens and a solid-state image capturing element. Generally, the imaging lens that is in a shape of rotation symmetry in an optical effective aperture is designed such that an MTF value is greatest in a center region where an image height is zero (see, for example, Patent Literature 1).
FIG. 4 is a graph showing an image height-MTF property of a conventional imaging lens. As shown in a full line of FIG. 4, the conventional imaging lens is designed such that the MTF value of the conventional imaging lens is greatest in the center region where the image height is zero and increase in the image height causes deterioration in the MTF value. This makes it possible to attain an imaging lens whose resolution performance is excellent in the center region.